Light-sensitive color-photographic material

ABSTRACT

COUPLERS FOR INCLUSION INTO THE SILVER HALIDE EMULSION LAYER OF A COLOR-PHOTOGRAPHIC MATERIAL; SAID COUPLER HAVING THE FORMULA:   R-S-CH2-(CH(-CH3))(N-1)-CO-NH-(X)(M-1)-B   WHEREIN R IS AN ALIPHATIC HYDROCARBON RESIDUE HAVING 8-18 CARBON ATOMS; B IS A COUPLER RESIDUE; X IS A GROUP BONDING B TO   R-S-CH2-(CH(-CH3))(N-1)-CO-NH-   AND M AND N ARE 1 OR 2.

United States Patent Office 3,580,721 Patented May 25, 1971 Int. Cl. Gtl3c 1/40 US. Cl. 96100 8 Claims ABSTRACT OF THE DISCLOSURE Couplers for inclusion into the silver halide emulsion layer of a color-photographic material; said coupler having the formula:

wherein R is an aliphatic hydrocarbon residue having 8-18 carbon atoms; B is a coupler residue; X is a group bonding B to and m and n are 1 or 2.

This invention relates to a light-sensitive color-photographic material. More particularly, the invention pertains to a light-sensitive color-photographic material containing, as a protected coupler, a novel coupler for forming a yellow, red or blue color dye image which is represented by the general formula wherein R is an aliphatic hydrocarbon residue having 8-18 carbon atoms; B is a coupler residue; X is a group capable of bonding (B) to and m and n are each either 1 or 2.

In order to be usable for commercial purposes, a protected coupler is required, in general, to satisfy the following conditions:

(1) The coupler should be high in purity and should be prepared according to a simple synthetic process from easily obtainable inexpensive materials.

(2) The coupler and a dye formed by color development should be readily soluble in high boiling solvents, such as tricresyl phosphate, dibutyl phthalate, etc. to give a high concentration solution.

(3) The coupler should have no detrimental effects, such as fogging, desensitization and the like, on a silver halide emulsion.

(4) Even after dispersion in a silver halide emulsion and after coating and drying, the coupler should give a stable photographic layer without crystallization.

(5) The coupler should have good dye formation, be excellent in spectral absorption characteristic of the resulting color-developed dye image, and be fast to heat, light, humidity and the like.

With a view toward satisfying the above requirements, many studies have been made and various couplers have been heretofore proposed. However, there has not been found a coupler which can satisfy the above requirements.

For example, the known coupler set forth in United States Pat. 2,801,171, which is represented by the formula is excellent 'in solubility for high boiling solvents, but is extremely expensive and is difficult to purify.

Further, the known coupler described in Japanese Patent publication No. 2,837/ 1964, which is represented by the formula is also excellent in solubility for high boiling solvents, but is expensive because the lipophilic component thereof must be synthesized in several steps.

In view of the above-mentioned prior art status, applicants have made various studies to find that the compound represented by the aforesaid general formula has excellent characteristics capable of satisfying the abovementioned requirements.

That is, the coupler employed in the present invention has such characteristics as mentioned below.

(1) It is quite readily soluble in a high boiling solvent such as dibutyl phthalate or tricresyl phosphate. Accordingly, the amount of high boiling solvent, based on the coupler, can be reduced, and a highly concentrated stable dispersion is obtainable.

(2) It is low in melting point and hence does not crystallize even in an emulsion or in a film formed after application and drying of the emulsion.

(3) It gives a color-developed dye image which has favorable spectral absorption characteristics and which is fast to light, heat and humidity.

(4) It has no such adverse effects as fogging and desensitization on the photographic characteristics of silver halide emulsion.

Moreover, the coupler employed in the present invention can be simply and economically prepared by using as a starting material a long chain alkyl mercaptan which is inexpensive and is easily obtainable. Accordingly, the novel coupler employed in the present invention is quite useful as a protected coupler and has substantially avoided the defects of the conventional couplers. Such excellent characteristics of the present coupler as mentioned above are considered ascribable to the existence of the long chain alkylthio fatty acid group.

The coupler employed in the present invention is obtained, in general, by forming an alkylthio fatty acid chloride from a long chain alkyl mercaptan and a methacrylic acid ester, or from a long chain alkyl mercaptan and a halogenated fatty acid, and then condensing said chloride with a coupler component having an amino group. Examples of the thus obtained coupler employed in the present invention are as shown below, but the compounds usable in the present invention are not limited thereto.

(IJCHs CH3 (M.P. 57-58 c.

(;M.P. 149 -151 c The following examples titled Synthesis A, B, C, D and E will serve to illustrate the synthetic procedures for the preparation of the couplers useful in this invention.

Synthesis A.Methyl fi-n-dodecylthio-a-methyl propionate In a 2-1. Erlenmyer flask, 202 g. (1 mole) of n-dodecyl mercaptan and .600 ml. of ethanol are charged. 36.2 g. of anhydrous sodium acetate, 33.8 ml. of water and 1 g. of hydroquinone are added thereto. After thorough mixing, 120 g. of methyl methacrylate are added, and the result ingmixtureis-heatedunder reflu-xfor over-6 hours. Theunreacted methyl methacrylate and ethanol are removed by distillation. The residue is diluted with 500ml. of water. An oily portion separated as an upper layer is extracted with 500 ml. of benzene andthe benzene extract is dried over anhydrous sodium sulfate and then distilled under reduced pressure to remove benzene therefrom. The desired product obtained is a transparent oily liquid having B.P. 168l74 C./lmm. and n 1.4646. Yield 266 g. (88%).

Synthesis B./8-n-dodecylthio-a;methyl propionic acid 266 g. (0.88 mole) of methyl fi-n-dodecylthio-u-methyl propionate are dissolved in 460 ml. of ethyl alcohol. To

the resulting solution, an aqueous solution of 90 g. of

R=C B.P. ll0ll5 C./1 mm. Hg; Yield 83%. R=C B.P. 204-208 C./ll mm. Hg; Yield 51.7%.

R=C B.P. 146 C./1 mm. Hg, yield 75.1%. R=C M.P. 58-60 C., yield 85.2%.

Synthesis D.fl-t-dodecylthioacetic acid chloride 24.2 g. (1.05 mole) of metallic sodium are dissolved in 480 ml. of ethanol. The resulting solution is cooled to room temperature and then mixed with 202 g. (1 mole) of t-dodecylmercaptan. After stirring the mixture at 65 70 C. for 15 minutes, 122.5 g. of ethyl monochloroacetate are added. The total mixture is heated under reflux for one hour. The reaction mixture is distilled to remove 440 ml. of the ethyl alcohol and the residue is diluted with Water. The separated oily upper layer is extracted with 1 1. benzene. The benzene extract is dried over anhydrous sodium sulfate and the benzene is removed by distillation under reduced pressure. 179 g. of a colorless oily liquid boiling at 126128 C./l.5 mm. Hg are obtained. Yield 62.3%. This oily liquid is subjected to hydrolysis in the same manner as in Synthesis B. A pale yellow, clear oily liquid is obtained, which shows the following elementary analysis for C H O S: Calcd. (percent): C, 64.58; H, 10.85; S, 1226. Found (percent): C, 63.94; H, 10.96; S, 12.20.

This oily liquid can be converted into the corresponding acid chloride in the same manner as in- Synthesis C.

Calcd. (percent): C, 66.63; H, 11.18; S, 1l.09 l?ound er'cnOfC, 66'. 6'4;"1'113'7'S, 1 138.

. Synthesis .CF15:n-dodecylthio-wrnethyl propionic let e.

mole) of fl-n-dodecylthio-a-rriethyl prop ionic H (3H3 Pv-S-OHzCH-COOCHa .vention is dissolved in a.high boiling. solvent havinga Synthesis E.a- 3-;8-n-dodecylthio-a-methylpropionamidob enzoyl) -2-methoxyacetanilide I To a solution of 17 g, of anhydrous sodiumacetate in 1 l. of glacial acetic acid, 57 g. (0.2 mole) of a-(3-aminobenzoyl)-2-methoxyacetanilide are added with stirring. Further, 6 2 g. of B-n-dodecylthio-a-methyl propionic acid chloride are added thereto at once. The mixture is heated at an internal temperature of 7075 C, for one hour. Then, the reaction mixture is poured into 5 l. of water. The oily layer as separated is extracted with 1 l. of ethyl acetate which is then removed by distillation under reduced pressure. There remains a pale yellow oily liquid which becomes solid by cooling. This is dissolved in 500 ml. of methanol and the resulting solution is passed through the layers of the ion-exchange resins, Amberlite CG- and CG-400. This methanolic solution is concentrated under reduced pressure to obtain a pale yellow pasty mass, which becomes solid by boiling together with 500 ml. of hexane. The solid is collected by suction and dried. 70 g. of pale yellowish White powder which is the coupler exemplified by (1) is obtained. Yield 62.5%.

In the same way, the coupler exemplified by (2) is prepared from a-(4-aminobenzoyl)-2-methoxy-5-ethoxycarbonyl acetanilide and t-dodecylthioacetyl chloride, and the coupler exemplified by (3) is prepared from a-(4- aminobenzoyl)-2-methoxyacetanilide and ,B-n-octadecylthio-a-methyl propionic acid chloride.

.1 produ in ,li ht-s n ye c lo -photo a hic. m terials by use of the above-mentioned couplers, any of the conventional processes may be employed.

For example, the coupleremployedin the present inboiling point of about C. (e.g. tricresyl phosphate or dibutyl phthalate), either alone or in admixture with av low boiling solvent (e.g. butyl acetate or butyl propionate), and then the solution is mixed with an aqueous gelatine solution containing a surface active agent. Subsequently, the mixed solution is emulsified by means of a high speed rotary mixer or a colloid mill. Thereafter, the resulting emulsion is added directly to a silver halide photographic emulsion and is then dried to remove a major portion of the low boiling solvent. Alternatively,

' the emulsion is once cold-set, finely cut and water-washed to remove the low boiling solvent, and is then added to a silver halide photographic emulsion. The thus obtained photographic emulsion is applied onto a suitable support,

such as a film base or baryta paper and is then dried, Typical as the developers usable for development of whereby a light-sensitive material can be obtained. In the light-sensitive photographic material of the present inthe above case, the amount of the coupler to be added vention are sulfates, sulfites and hydrochlorides of:

to the silver halide photographic emulsion is preferably 15-100 g, per mole of silver halide. However, the amount 5 Y -P-P Y of the coupler is not always limited to said range. Y -fiy y After exposure to light, the light-sensitive material obaminoaniline, tained in the above manner is developed with a para- N-ethyl-N- y y y Y -Pp y phenylenediamine-type developing agent, and is then N-ethyl-N-hydroxyethyl-p-phenylenediamine, and bleached, fixed and freed from silver to obtain a high 10 N,N-diethyl-2-methyl-p-phenylenediamine. density, colored image excellent in spectral absorption characteristics and in transparency. Further, the coupler Comp in melting Point between the 10118 Chain does not suffer from crystallization, and therefore there lkyl fatty acid residue-Containing couplers p y is no scattering of the light, and the transparency of unin the present invention and known couplers similar in exposed area also is excellent. 15 structure thereto are shown in the following tables:

TABLE 1.-COMPARISON IN MELTING POINT BETWEEN THE COUPLER EXEMPLIFIED BY (1) AMONG THE COU- PLERS EMPLOYED IN THE PRESENT INVENTION AND A KNOWN COUPLER SIMILAR IN STRUCTURE THERETO Coupler Structural formula M.P. C.)

Coupler exemplified by (1) Il-C1zH25s CH2?HC ONH- (1) CH; 106-108 0 0m 0 0 NH- Coupler disclosed in US. Pat. 2,875,057 t-mm-Q-o cure ONH OH; 126-127 C1120 ONH TABLE 2.COMPARISON IN MELTING POINT BETWEEN THE COUPLER EXEMPLIFIED BY (8) AMONG THE COU- PLERS EMPLOYED IN THE PRESENT INVENTION AND A KNOWN COUPLER SIMILAR IN STRUCTURE THERETO Coupler Structural formula MP. 0 C.)

Coupler exemplified by (8) n-C1zHz S'CH2CHCONH 75-77 Coupler disclosed in US. Pat. 2,618,614 t-C H1i 0 CHzC ON H- 138-139 sHn ONH-|C|OH l Cl TABLE 3.-COMPARISON IN MELTING POINT BETWEEN THE OOUPLERS EXEMPLIFIED BY (17) AMONG THE COUPLERS EMPLOYED IN THE PRESENT INVENTION AND A KNOWN COUPLER SIMILAR IN STRUCTURE THERETO Coupler Stmctural formula M.P. 0.)

Coupler exemplified by (17) n-C12Hz SOH2GH-OONH -01 57-58 (|)Ii.' Coupler disclosed in U.S. Pat. 2,801,171 t-Cfllg-Q-O CHCONH- Cl 123424 lzHg t-C Hu CH;

10 As is clear from the above tables, the couplers emcouplers employed in the present invention are excellent ployed in the present invention are far lower in melting in solubility for high boiling solvents are set forth in the point than the known couplers, and hence do not crystables below. Each test was effected by measuring the tallize in emulsions or in photographic layers formed by temperature at which 1 g. of a coupler was dissolved in applying the emulsions to suitable support. Thus, the 2 ml. of dibutyl phthalate, and comparison in solubility light-sensitive photographic materials of the invention between the present couplers and known couplers were are excellent in stability and transparency. made on the basis of the thus measured temperature.

Further, the results of tests showing the fact that the TABLE 4.COMPARISON IN SOLUBILITY BETWEEN THE COUPLER EXEMPLIFIED BY (1) AMONG THE COUPLERS EMPLOYED IN THE PRESENT INVENTION AND A KNOWN COUPLER SIMILAR IN STRUCTURE THERETO Dissolved temperature Coupler Structural formula O Coupler exemplified by (1) n"Cl2H25 s CHz-CH-C ONH- 0 CH 50 3 oooH2ooNH Coupler disclosed in U.S. Pat. 2,875,057 t-C 5liiio onto 0 NH@ 0 CH3 so TABLE 5.COMPARISON IN SOLUBILITY BETWEEN THE COUPLER EXEMPLIFIED BY (8) AMONG THE COUPLERS EMPLOYED IN THE PRESENT INVENTION AND A KNOWN COUPLER SIMILAR IN STRUCTURE THERETO Dissolved temperature Coupler Structural formula C Coupler exemplified by (s) n-C 12H25-S OH2(|3HO ONE-Q 0N1l-fi--- 1H2 Cl C1 Coupler disclosed in U.S. Pat. 2,618,614 tC Hi1O CHzOONH-Q I I ecni o ONHC-CH2 cl Cl TABLE firCOMPARISON IN SOLUBILITY BETWEEN THE COUPLERS EXEMPLIFIED BY (17) AMONG THE COUPLERS EMPLOYED IN THE PRESENT INVENTION AND A KNOWN COUPLER SIMILAR IN STRUCTURE THERETO Dissolved temperature Coupler Structural formula (3,)

Coupler exemplified by (17) n-Ci2IIz5- S C H2- CIIC ONH -01 45 l Coupler disclosed in U.S. Int. 2,801.171 t-C H O CHCONH- Cl As is clear from the above results, the couplers employed in the present invention are excellent also in solubility for high boiling solvents as compared with the known couplers and hence are quite useful as protected couplers. Moreover, they give such advantages as the increase in developed color density and the reduction in amounts of couplers. Accordingly, the light-sensitive photographic materials of the present invention have excellent photographic characteristics in color reproductivity and granularity.

The present invention is illustrated below with reference to examples, but the examples are merely illustrative and the invention is, of course, not limited thereto.

EXAMPLE 1 200 g. of the coupler exemplified by (1) were added to a liquid mixture comprising 200 ml. of dibutyl phthalate and 600 ml. of butyl acetate, and was completely dissolved by heating to 80 C. The solution was mixed with 100 m1. of a 10% aqueous solution of Alkanol B (alkylnaphthalene sulfonate produced by E. I. du Pont de Nemours & Co.) and 2000 ml. of a 5% aqueous solution of gelatine. Subsequently, the mixture was subjected to a colloid mill to form a coupler dispersion.

This coupler dispersion was added to kg. of a high speed gelatino silver iodobromide photographic emulsion, and was applied onto a film base, followed by drying, to obtain a light-sensitive photographic material having a stable light-sensitive layer.

This light-sensitive material was exposed according to an ordinary procedure and was developed at C. for 10 minutes by use of a developer of the following composition:

G. N,N-diethyl-p-phenylenediamine hydrochloride 2.5 Anhydrous sodium sulfite 2.0 Sodium carbonate (monohydrate) 82.0 Potassium bromide 2.0

Water to make 1000 ml.

The developed material was treated with a stopping solution and then with a fixing solution, was washed with water for 10-15 minutes, and was treated for 5 minutes in a bleaching bath of the following composition:

G. Potassium ferricyanide 100 Potassium bromide 50 Water to make 1000 ml.

The bleached material was further washed with Water for 5 minutes and was then fixed for 5 minutes in a fixing bath of the following composition:

Sodium thiosulfate (pentahydrate)250 g. Water to make 1000 ml.

Subsequently, the fixed material was water-washed for 20- minutes and was then dried to obtain a clear yellow dye image having a maximum absorption at 440 m In the same manner as above, the couplers exemplified by (8) and (14) were individually added to silver halide emulsions, were applied onto supports and were then dried to obtain light-sensitive photographic materials. After exposure to light, the thus obtained photographic materials were subjected to the same color development treatment as mentioned above to obtain clear magenta and cyan dye images having maximum absorptions at 540 m and 680 m respectively.

EXAMPLE 2 100 g. of the coupler exemplified by (2) were added to a mixture comprising 100 ml. of tricresyl phosphate and 300 ml. of butyl acetate, and was completely dis- 12 solved by heating to 60 C. The solution was mixed with 50 ml. of a 10% aqueous solution of alkanol B and 2000 ml. of a 5% aqueous solution of gelatine. Subsequently, the mixture was subjected to a colloid mill to form a coupler dispersion. This coupler dispersion was added to 5 kg. of a high speed gelatino silver iodobromide emulsion and was applied onto a film base, followed by drying, to obtain a light-sensitive photographic material having a stable photographic layer.

This light-sensitive material was exposed and was developed at 20 C. for 10 minutes by use of a developer having the following composition:

Metol 3.0 Anhydrous sodium sulfite 60. Hydroquinone 6.0 Anhydrous sodium carbonate 50.0 Potassium bromide 1.0

Water to make 1000 ml.

The developed material was subjected to ordinary stopping and hardening treatment, was washed with water, and was then subjected to re-exposure by use of a white light.

The thus treated material was developed at 20 C. for 12 minutes by use of a developer of the following composition:

N,N-diethylparaphenylenediamine hydrochloride 5.0 Anhydrous sodium sulfite 2.0 Sodium carbonate (monohydrate) 82.0 Potassium bromide 1.0 Water to make 1000 ml.

EXAMPLE 3 g. of the coupler exemplified by (17) were mixed with 200 ml. of dibutyl phthalate and was completely dissolved at 50 C. The solution was mixed with 50 ml. of a 10% aqueous solution of Alkanol B and 2000 ml. of a 5% aqueous solution of gelatine. Subsequently, the mixture was passed several times through a colloid mill to form an emulsified dispersion. This dispersion was added to 5 kg. of a gelatino silver chlorobromide emulsion, and was applied to a baryta paper, followed by drying, to prepare a light-sensitive material.

This light-sensitive material was exposed and was the developed at 20 C. for 10 minutes in a bath of the following composition:

G. N-ethyl-N-hydroxyethyl-p-phenylenediamine sulfate 2.5 Anhydrous sodium sulfite 2.0 Hydroxyamine hydrochloride 1.0 Sodium carbonate 82.0 Potassium bromide 2.0 Water to make 1000 ml.

The developed material was dipped in a stop bath comprising 10 ml. of glacial acetic acid, 3.0 g. of caustic soda, and 1000 ml. of water, and was then immediately dipped for 4 minutes in an acidic fixing bath containing a hardener. Subsequently, the fixed material was washed with 13 water for minutes and was then bleached at C. for 8 minutes in a bath of the following composition:

G. Disodium ethylenediamine tetraacetate 40.0 Ferric chloride '3 0.0 Sodium carbonate (monohydrate) 20.0 Potassium bromide 30.0

Sodium thiosulfate (pentahydrate) 200.0 Water to make 1000 ml.

The bleached material was washed with water for 20 minutes and was then dipped for 2 minutes in a stabilizing bath, followed by drying, to obtain a cyan dye image having a maximum absorption at 680 m which was excellent in resistance to light and humidity.

What we claim is:

1. A light-sensitive color-photographic material comprising a compound represented by the general formula wherein R is an aliphatic hydrocarbon residue having 8-l8 carbon atoms; B is a coupler residue; X is a group bonding (B) to and m and n are each either 1 or 2, is incorporated as a protected coupler in the color-photographic silver halide emulsion layer of said color-photographic material.

14 5. A light-sensitive color-photographic material as claimed in claim 1, wherein said compound is represented by the chemical formula claimed in claim 1, wherein said compound is represented by the chemical formula 7. A light-sensitive color-photographic material as claimed in claim 1, wherein said compound is represented by the chemical formula 2. A light-sensitive color-photographic material as claimed in claim 1, wherein said compound is represented by the chemical formula 3. A light-sensitive color-photographic material as claimed in claim 1, wherein said compound is represented by the chemical formula 4. A light-sensitive color-photographic material as claimed in claim 1, wherein said compound is represented by the chemical formula 8. A light-sensitive color-photographic material as claimed in claim 1, wherein said compound is represented by the chemical formula References Cited UNITED STATES PATENTS 2,772,162 11/ 1956 Salminen et al 96-l00X 3,133,815 5/1964 Greenhalge 96100X 3,341,331 9/1967 Kimura et a1. 96-100X 3,369,899 2/1968 De Cat et al. A 96-100X 3,409,439 11/ 1968 Yoshida et al 96-100 WILLIAM D. MARTIN, Primary Examiner T. G. DAVIS, Assistant Examiner US. Cl. X.R. 

